Photographic developer containing an aralkylamine and process of development



Patented July 11, 1950 PHOTOGRAPHIC DEVELOPER CONTAINING AN ARALKYLAMINE .AND PROCESS OF DEVELO?MENT William L. Wasley, Bingharntn, N. Y., .assignor 'to General'Aniline & Film Corporation, New

York, N. Y., 'a. corporation. of Delaware NoDrawing. Application August 26, 1947,

- Serial No. 170,750

'12 Claims. (01. 95--ss-) This invention relates to photographic de.-

velopers and particularly to accelerators for photographic developers.

It is wellknown that various amines, such as primary and secondary alkyl and alkylene amines containing from 3 to '7 carbon atoms, and heterocyclic amines, may be added to photographic black and white and color developing solutions for the purpose of increasing the rate of develop ment. In other words, these amines accelerate the development so as to allow the developing agent to form the image (silver or color image) as rapidly as possible. p

Although developing solutions containing such amines out the developing timetfrorn about 20-30 minutes to 12-15 minutes, such a decrease is insufficient where large scale operations are involved, as in commercial processing where time is of the essence.

It is, therefore, an object of the present invention to provide a blackand white and color developer having an increased rate of development so that the developing time is substantially decreased to less than half of the normal time.

Other objects will appear hereinafter.

These objects are accomplished by adding an aralkylamine to the usual black and white developer, and to a color-forming developer in which a primary aromaticamine is used as the developing agent. It has been ifound that in developing color images in multi-color photographic layers containing color-formers fast to diffusion, as disclosed in United States Patents 2,178.612; 2,179,228, 2,179,234; 2,179,238-9; 2,179,244; 2,186,719; 2,186,85l-2; 2,1-86332-3-4; 2,186,849; 2,200,366; 2,280,722; 2,292,575; 2,303,928 and 2,307,399, with a color'de'velop'er containing an aralkyl amine, the developing time is cut from 20-30 minutes to 2-10 minutes}. All of the layers are simultaneously developed, and the dye images formed are of excellent quality.

The developing time with black and white developers, for instance, solutions of hydroquinone and Metol and of 'hydroquinone and Elon, and the like, is also cut by more than half without causing fog when such solutions contain an aralkyl amine.

The aralkylamines to be employed in accord ance with the present invention are represented wherein R is methyl .or ethyl and a positive integer ofpfrom 2 to .3.

The following are examples ofsuch aralkyl amines: 7 e

CHzCHW'H:

fi-plienylethylamine dHjCHzCHzNH: I

'r-phenylpropylamine I GHa H-NH:*

q-plienylethylamine CaHs (lit-NH,

ip nylp p lam The amines are soluble'in water and in alkaline developers, and'may he used "in specified amounts. The most useful concentrations in 'blacka'rrd white developersrange from about 1.0 cc. to about '10 cc. per liter. In color developers the -most useful concentrations range from about 2.0 cc. to 7.0 cc. per liter. Concentrationsgreater than 7.0 cc per liter of color developer have the tendency to distort the color balance of the color film. As illustrative developing solutions containing such aralkylaanines, the following are given:

Example I v v v iMetol grams Sodium .sulfite ,(anhydrous). .sdo Hydroquinone do s Sodium carbonate (monohydrate). .d0f "Q .Potassium .metabisulfite .d.o s Potassium. .bromide do H a-IPhenylethylamine .cc 2.5 Water to make liter 1.0

This tank developer gives, on developmental C. of the usual roll film, a soft negative in about 4-6 minutes after fixing and washing. The time required to develop a similar roll in' title same developer and at the same temperature, containing no a-phenylethy'lamine, ranges from 15 to 20 minutes. Increasing the concentration of the a-phenylethylamine to 5.0 cc. per liter efiects' a further decrease in time.

The following developer requires 30 minutes at 20 C. to'give a satisfactory degree of color de By theaddition of cc. of p-phenylethylamine to the foregoing developing solution, a ,color paper of excellent color rendition is developed in 5 minutes. Increasing the concentration of the amine further reduces the time of development.

The color paper (photographic multi-layer element) utilized in the foregoing example, consists of an integral tripack emulsion coated on either the usual paper base, or a clear cellulose acetate velopment with color paper! Sodium hexametaphosphate grams; 1.0 Sodium bisulfite do 2.0 N-N-bis(,3-hydroxylethyl) p:-phenylenedi-. H amine sulfate -grams 6.3 Sodium carbonate do 100 U Hydroxylamine hydrochloride do ;s 1.0 i Potassium bromide do 1.0 Water to make liter 7 1.0

or nitrate film base, or insome cases an opaque white film base. 'Each of the emulsion layers is sensitized to one of the primarycolors of light; namely, blue, green and red.} The top layer is blue sensitive. A filter layer, yellow in color and blue absorbing, lies under the top layer. Below this filter layer, lies a green sensitive emulsion layer, and below this a red sensitive emulsion layer. Each of the three silver-halide emulsion layers contains dye-forming compounds which unite during the development of a silver image in an aromatic amine developing agent to form a dye with the oxidation product of the developing agent. As silver is also formed during de- Example III The following developer requires 19 minutes at 20 C. to give a satisfactory degreeof color development with color paper:

, .Sodium hexametaphosphate grams 1.0 -Sodium bisulfite do .20 ,N ethyl-N-hydroxyethyl p phenylenedij .aminejsulfate grams f 6.7 Sodium carbonate do 100 .Hydroxylamine hydrochloridedo .l.0 Potassium bromide do 1.0 Water to make; liter 1.0

. By the addition of 2.5 cc. of a-phenylpropylamine to the foregoing developing solution,.a color paper of excellent color rendition is developed in 4 minutes. Increasingthe concentration of the amine to 6 cc. reduces the time of development to 2 minutes with the same results.

' Example IV The color developer of the preceding example with the addition of 5.0 cc. of e-phenylethylamine developed ;:a multi-layergcolorgfllm sheet, of the reversal type and containing color-formers fast to diifusion, in 10 minutes at 20 C'.; whereas without the aphenylethylamine the time required .to color develop the. said film sheet is over 30 "minutes.

The aralkylamines described herein have the advantage that they effect a simultaneous increase in contrast and greater reduction in developing'time than other amines heretofore used for this purpose.

What I claim is: 1. Analkaline photographic developer for silver halide emulsions comprising an aqueous solution of a silver halide developing agent, an inorganic alkali and an aralkylamine selected from the class consisting of those' corresponding to the following formulae:

(0 a) ..NHa

and

R l on-NH,

wherein R is a group selected from the class consisting of methyl and ethyl groups, and n is a positive integer of from 2 to 3.

2. An alkaline photographic developer for silver-halide emulsions comprising an aqueous so lution of a, silver halide developing agent, an inorganic alkali and an aralkylamine characterized by the following formula:

3. An alkaline photographic developer for silver-halide emulsions comprising an aqueous solution or a silver-halide developing-agent, an inorganic alkali and an aralky-lamine characterized by the following formula:

4. ,An alkaline photographic developer for sil ver-halide emulsions comprising an aqueous so lution of a silver-halide developing agent, an inorganic alkali and an aralkylamine characterized by the following formula:

5. In the development of a photographic negative the step comprising the'development of an exposed silver-halide emulsion in an aqueous solution of an alkaline silver halide developing agent, said solution containing an inorganic alkali and a, developing accelerator selected from the class consisting of aralkyl amines to the following formulae:

corresponding and wherein R is a group selected from the class con- 7. In the development of a photographic negative the step comprising the development of an exposed silver-halide emulsion in an aqueous solution of an alkaline silver halide developing agent, said solution containing an inorganic alkali and a developing accelerator characterized by the formula:

8. In the development of a photographic negative the step comprising the development of an exposed silver-halide emulsion in an aqueous solution of an alkaline silver halide developing agent, said solution containing an inorganic alkali and a developing accelerator characterized by the formula:

9. A color-forming photographic developer comprising an aqueous solution of a primary aromatic amino developing agent, an inorganic alkali and an aralkylamine selected from the class consisting of those corresponding to the followin formulae:

and

R .1 H-NH:

wherein R is a group selected from the class consisting of methyl and ethyl groups, and n is a positive integer of from 2 to 3.

10. A color-forming photographic developer comprising an aqueous solution of a primary aromatic amino developing agent, an inorganic alkali and an aralkylamine characterized by the following formula:

11. A color-forming photographic developer comprising an aqueous solution of a primary aromatic amino developing agent, an inorganic alkali and an aralkylamine characterized by the following formula:

CHzC Ha-NH:

12. A color-forming photographic developer comprising an aqueous solution of a primary aromatic amino developing agent, an inorganic alkali and an aralkylamine characterized by the following formula:

WILLIAM L. WASLEY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,371,740 Dearing et a1 Mar. 20, 1945 2,410,644 Fierke et al Nov. 5, 1946 

1. AN ALKALINE PHOTOGRAPHIC DEVELOPER FOR SILVER HALIDE EMULSIONS COMPRISING AN AQUEOUS SOLUTION OF A SILVER HALIDE DEVELOPING AGENT, AN INORGANIC ALKALI AND AN ARALKYLAMINE SELECTED FROM THE CLASS CONSISTING OF THOSE CORRESPONDING TO THE FOLLOWING FORMULAE: 